AngleBetween inconsistent behaviour between 2d and 3d versions

AngleBetween 3D version gives NAN when fed with same data as 2D version

I think 3D version expects normalised inputs?
Confusing because the helppatch shows the 2D version so you don’t expect to need the normalisation when you deploy the 3D one.

Also see related

This is also related to the last point in the list that I’ve written up here: